• 한국정보디스플레이학회:학술대회논문집
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• 2007.08b
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• pp.1344-1347
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• 2007

We have fabricated bottom gate TFTs with active layers of amorphous/microcrystalline Si double layers (DL). Dynamic electric stresses were applied to DL TFTs and a-Si TFTs to compare their degradation characteristics. The DL TFTs were more stable under dynamic stresses than a-Si TFTs.

• Journal of Information Display
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• v.4 no.4
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• pp.1-3
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• 2003

For excimer laser annealing (ELA), energy density, number of pulses, beam uniformity, and condition of initial amorphous Si (a-Si) films are significant factors contributing to the final microstructure and the performance of low-temperature polycrystalline Si (LTPS) TFTs. Although the process and equipment have been significantly improved, the environmental factors associated with initial amorphous Si (a-Si) films and process conditions are yet to be optimized.

• Proceedings of the Korean Vacuum Society Conference
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• 1999.07a
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• pp.63-63
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• 1999

The stability of hydrogenated amorphous silicon (a-Si:H) films under the light soaking are very important since the applications of a-Si:H films are solar cells, color sensors, photosensors, and thin film transistors(TFTs). We found the changes of the electric conductivity and the conductivity activation energy (Ea) of a-Si:H films by argon radical annealing. The deposition rate of a-Si:H films depends on the argon radical annealing time. The optical band gap and the hydrogen contents in the a-Si:H films are changes along the argon radical annealing time. We will discuss the microscopic processes of argon radical annealing in a-si:H films.

• 한국정보디스플레이학회:학술대회논문집
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• 2000.01a
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• pp.151-152
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• 2000

For excimer laser crystallization (ELC), energy density, number of pulses, beam uniformity, and condition of initial amorphous Si (a-Si) films are significant factors contributing the final microstructure and the performance of low-temperature polycrystalline Si TFTs. The process and equipment have been achieved a significant improvement, but still, environmental factors associated with initial amorphous Si (a-Si) films and process conditions need to be optimized.

• Journal of the Korean institute of surface engineering
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• v.17 no.2
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• pp.59-63
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• 1984

하루가 다르게 발전하고 있는 최첨단기술인 電子材料의 膜 형성기술중 amorphous silicon(a-Si) 을 電氣鍍金으로 얻는 방법을 소개하였다. 1975년 a-Si이 p-n制御가 가능한 半導體임이 확인된 이후, 큰 면적의 太陽電池, 複寫機用 感光體薄膜, transistor array 등의 응용이 착착 진행되고 있다. 종래의 單結晶실리콘 半導體를 이용한 太陽電池는 가격면에서 비싸 경제성이 적었던 것이 a-Si의 등장으로 小型 計算機등에 까지 a-Si을 사용한 太陽電池로 電源을 대체하기 시작하여 빠른속도로 시장이 확대되어가고 있다. 특히 a-Si는 햇빛은 물론 형광등의 파장범위에서도 光應答을 하기때문에 太陽電池로서 일상생활에 광범위하게 이용될 전망이 있다. 이 a-Si의 제법으로는 蒸着法, sputtering 法, glow 放電分解法등 매우 복잡한 장치를 이용하여 膜을 형성시키고 있으나 장치가 간단하고 값싼 電氣鍍金法도 가능성이 있음이 기초적으로 알려지기 시작하였다. 본 자료는 일본 三重大學의 Y.Takeda와 O.Yamamoto가 "Amorphous Silicon의 電解析出"이란 제목으로 최근발간된 학술잡지 [電氣化學 52(7),460(1984)]에 실린 글로서 電氣都給方法이 최첨단기술분야에도 일익을 담당하고 있어 흥미로와 여기에 소개하였다.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.32A no.6
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• pp.51-58
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• 1995

Major limiting factors in the linear scaling down of the shallow source/drain junction are the boron channeling effect and the Si cosumption phenomenon during silicidation. We can solve these problems by As preamorphization of the predeposited amorphous Si layer. The predeposited amorphous Si layer made the junction depth decrease to nearly the thickness value of the layer and was effectively utilized as the cosumed Si source during Ti silicidation. This method was applied to the actual fabrication of PMOSFET through SES (selectricely etched Si) techology.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09b
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• pp.786-787
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• 2006

The magnetic inductance of nanocrystalline $Fe_{73}Si_{16}B_7Nb_3Cu_1$ and an amorphous FeSiB powder sheet has been investigated to identify RFID performance. The powder was mixed with binder and solvent and tape-casted to form films. Results show annealing significantly influenced on the inductance of the material. The surface oxidation of the particles was the main reason for the reduced inductance. The maximum inductance of $Fe_{73}Si_{16}B_7Nb_3Cu_1$ alloy was about $88{\mu}H$ at 17.4 MHz, about 65% greater compared to the FeSiB alloy. The higher inductance in the nanocrystalline alloy indicates it may be used as a potential replacement of current RFID materials.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.322.1-322.1
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• 2014

Many research groups have studied tandem or multi-junction cells to overcome this low efficiency and degradation. In multi-junction cells, band-gap engineering of each absorb layer is needed to absorb the light at various wavelengths efficiently. Various absorption layers can be formed using multi-junctions, such as hydrogenated amorphous silicon carbide (a-SiC:H), amorphous silicon germanium (a-SiGe:H) and microcrystalline silicon (${\mu}c$-Si:H), etc. Among them, ${\mu}c$-Si:H is the bottom absorber material because it has a low band-gap and does not exhibit light-induced degradation like amorphous silicon. Nevertheless, ${\mu}c$-Si:H requires a much thicker material (>2 mm) to absorb sufficient light due to its smaller light absorption coefficient, highlighting the need for a high growth rate for productivity. ${\mu}c$-SiGe:H has a much higher absorption coefficient than ${\mu}c$-Si:H at the low energy wavelength, meaning that the thickness of the absorption layer can be decreased to less than half that of ${\mu}c$-Si:H. ${\mu}c$-SiGe:H films were prepared using 40 MHz very high frequency PECVD method at 1 Torr. SiH4 and GeH4 were used as a reactive gas and H2 was used as a dilution gas. In this study, the ${\mu}c$-SiGe:H layer for triple solar cells applications was performed to optimize the film properties.

• The Korean Journal of Ceramics
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• v.6 no.2
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• pp.155-158
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• 2000

NMR study has been used for measuring precise quantity of the amorphous phase in the $Si_3N_4$powder. Care must be taken to allow the $^{29}$Si nuclear spin system to fully relax between pulses in order to make the signals proportional to the number of nuclei in each phase. $^{29}$Si MAS spectrum was decomposed into the three spectra of $\alpha$-, $\beta$-, and amorphous $Si_3N_4$assuming pseudo-Voigt function. Moreover, the Rietveld analysis of the powder X-ray diffraction data was performed to measure quantity of crystalline phases as $\alpha/\beta$ ratio.

• Korean Journal of Materials Research
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• v.15 no.12
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• pp.765-772
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• 2005

PAS(Plasma Activated Sintering) process was tried to apply for the fabrication of BMG(Bulk Metallic Glasses) of $Ni_{57}Zr_{20}Ti_{18}Si_5}\;and\;Ni_{57}Zr_{20}Ti_{18}Si_3Sn_2$ from the as-atomized amorphous powder. Compressive strength for the BMG(bulk Metallic Glasses) of $Ni_{57}Zr_{20}Ti_{18}Si_5$ were lower than those of BMG rods produced by warm extrusion ,or copper mold casting method. Microstructural examination by optical microcope, SEM ana EDS showed that oxidation had occurred during PASintering. In order to prevent the powder from the oxidation during PASintering, Ni coating for $Ni_{57}Zr_{20}Ti_{18}Si_5$ amorphous powder by electroless-plating method was performed. Microstructural examination for Ni coated layers after PASintering indicated that the Ni coating had been so effective to prevent powder from oxidation during PASintering. Sintering behaviors of $Ni_{57}Zr_{20}Ti_{18}Si_3Sn_2$ represent the same as those of $Ni_{57}Zr_{20}Ti_{18}Si_5$.